To unlock the Debut trophy in Layers of Fear 2, you will need to find your first movie poster in the game. There are 15 movie posters in total (3 per act). Finding all 15 unlocks the trophy below. You can find a video guide for all of the locations there.
The first movie poster you come across is in Act 1 when you have to solve a puzzle with some mannequins on rotating platforms. Once you solve the puzzle, go through the small opening to reach a second stage. On the back wall at the top of some small stairs, you can find the Remember Her movie poster.